High
F.62 on Vaillant Turbomax 824/828

Your boiler has detected that a flame is still being sensed even after it should have switched off, which is a safety issue that prevents it from restarting.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Flame rectification present 4 secs. after gas valve turns off Check gas valve, burner tubes and injectors or electronics defect

From this model's manual
Verified against the Vaillant Turbomax 824 828 installation & service manual, page 40.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.61View →F.63View →

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